THE DEFENSIVE FUNCTION OF PERSECUTORY DELUSIONS EVIDENCE FROM ATTRIBUTION TASKS

Abnormalities of 'social' reasoning were investigated in patients suff ering from persecutory delusions and in matched depressed and normal c ontrols using transparent (obvious) and opaque (unobvious) tests of at tributional style. Whereas depressed and normal subjects yielded simil ar causal inferences for both attributional measures, the deluded subj ects showed a marked shift in internality, attributing negative outcom es to external causes on the transparent Attributional Style Questionn aire but, on the more opaque Pragmatic Inference Task, attributing neg ative outcomes to internal causes and thus showing a cognitive style r esembling that of the depressed group. This finding, interpreted in te rms of explicit versus implicit judgements, supports the hypothesis th at delusions function as a defence against underlying feelings of low self-esteem.